This application claims the priority of Japanese Patent Applications No. 2001-48243 filed on Feb. 23, 2001 which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an electronic endoscope system. More particularly, the present invention relates to a configuration of an electronic endoscope system used by connecting any type of electronic endoscope corresponding to an application portion etc., an electronic endoscope having different optical characteristics, or the like to a common processor.
2. Description of the Related Art
Conventionally, various types of electronic endoscopes have been manufactured to be applied to different portions of human body etc. These electronic endoscopes have a configuration such as to be connected detachably to a processor, and an observed object can be displayed on a monitor by means of an image signal generated from this processor. Specifically, an objective optical system and a CCD (Charge Coupled Device), which are an objective optical system and a solid-state image sensor, are provided in the distal end portion of the electronic scope. By driving this CCD, signals in color pixel units of, for example, cyan (Cy), magenta (Mg), green (G), and yellow (Y) are obtained, and these signals are subjected to image processing such as signal amplification, conversion into color-difference signal and luminance signal or color signal of R (red), G (green), and B (blue), and gamma control with a signal processing circuit of an electronic endoscope and a processor.
In the image processing of the above-mentioned conventional electronic scope, image processing data considering the image pickup conditions specific to the individual electronic scope are stored, and the above-mentioned various processing is performed based on these data. For example, the image processing data include an amplification factor or correction factor for the above-mentioned color signal of Cy, Mg, G and Y, luminance signal, color-difference signal, color signal of R, G and B, etc., a correction factor for gamma correction, or the like. These image processing data are stored in a memory on the electronic scope side and a memory on the processor side, and necessary factor data etc. are read in a predetermined circuit, by which signal processing is performed.
Specifically, since the optical characteristics of the objective optical system and CCD disposed in the distal end portion of the electronic scope differ depending on the type of electronic scope, and also somewhat differ according to the manufacture, the image processing data specific to the electronic scope are stored in the memory on the electronic scope side, and thereby an image with high color reproducibility is formed by the data on the electronic scope side and the data on the processor side.
However, since the image signal processing using the above-mentioned electronic endoscope system is performed by both of the electronic scope and the processor, the processing can be performed only by a plurality of predetermined electronic endoscopes and a processor designed to correspond to these electronic endoscopes. If a new type or different type of electronic endoscope system is developed and manufactured and the signal processing conditions (image processing data) on the processor side are changed, the white balance is lost. Therefore, there arises a problem in that an old type of electronic scope cannot be connected to a new type or different type of processor, so that the electronic scope cannot be used effectively.
The present invention has been made to solve the above problem, and accordingly an object thereof is to provide an electronic endoscope system in which the compatibility with an old type of electronic endoscope can be maintained even when a new type or a different type of system is manufactured.
To achieve the above object, the present invention provides an electronic endoscope system comprising any type of electronic endoscope having a memory for storing data specific to the scope for image processing for a signal obtained using an image pick-up device; and a processor configured to be connectable with the electronic endoscope, wherein the processor is provided with a signal processing circuit for receiving an image signal from the electronic endoscope for further image processing and a white balance control circuit for carrying out white balance control based on the picked-up image of a white object to control new image processing data based on this control to be written in a memory of the electronic endoscope.
Also, in the present invention, the white balance control circuit of the processor determines whether or not image processing data compatible with the processor are present by referring to data in the memory of the electronic endoscope, and if the compatible image processing data are not present, the white balance control circuit can carry out the white balance control and writing control.
According to the above-described configuration, the white balance control circuit determines whether or not image processing data compatible with the processor are present in the connected electronic endoscope, for example, at the time when power is turned on. If the compatible data are not present, this fact is displayed to prompt the user etc. to carry out white balance control.
Next, the user etc. select white balance control from a menu screen etc., and pick up the image of a white board. Then, the white balance control is carried out by the control circuit, and the image of observed object is displayed under the condition that the control has been carried out. Based on, for example, the user""s operation for determining writing, new image processing data at the time of white balance control is additionally written in the memory of the electronic endoscope. Subsequently, signal processing is performed based on the new data.
Further, in the present invention, in the case where an electronic endoscope using a light source as the standard, the light source being different from a light source used in the processor as the standard, is connected to the processor, light source correction data for compensating the difference between the light sources are preferably written in the memory together with the image processing data.